Intramedullary nails were first used in the 1930s. These early nails were inserted into the intramedullary canal of the bone. The result was immediate fixation of fractures, reduction in patient recovery time, increased mobility, and improved quality of life. Multiple examples of such nails are present in the prior art.
But rotation of the inserted nails was a problem. Rotation would result in the nail being in a position different than that chosen by the surgeon. To address this issue, screws were installed that held plates against the outer surface of the bone, used to fix the rotational position of the bone. The plates changed the profile of the bone, potentially causing irritation to surrounding tissue.
The most significant problem caused by the requirement of additional screws is the additional time required under exposure to x-ray radiation. The installation of each screw requires additional x-rays to verify location, depth, and so forth. X-ray radiation is damaging to the patient, but is especially troublesome to the surgeon because each surgeon must perform many of these surgeries. Thus, any reduction in x-rays is highly beneficial.